The most commonly used SQL command is SELECT statement. The
SQL SELECT statement is used to query or retrieve data from a table in the
database. A query may retrieve information from specified columns or from all
of the columns in the table. To create a simple SQL SELECT Statement, you must
specify the column(s) name and the table name. The whole query is called SQL
SELECT Statement.
table-name is the name of the table from which the information is retrieved.
Syntax of SQL SELECT Statement:
SELECT column_list FROM table-name
[WHERE Clause]
[GROUP BY clause]
[HAVING clause]
table-name is the name of the table from which the information is retrieved.
column_list includes one or more columns from which data is
retrieved.
The code within the brackets is optional.
database table student_details;
id
|
first_name
|
last_name
|
age
|
subject
|
games
|
100
|
Rahul
|
Sharma
|
10
|
Science
|
Cricket
|
101
|
Anjali
|
Bhagwat
|
12
|
Maths
|
Football
|
102
|
Stephen
|
Fleming
|
09
|
Science
|
Cricket
|
103
|
Shekar
|
Gowda
|
18
|
Maths
|
Badminton
|
104
|
Priya
|
Chandra
|
15
|
Economics
|
Chess
|
For example, consider the table student_details. To select the
first name of all the students the query would be like:NOTE: These database tables are used here for better explanation
of SQL commands. In reality, the tables can have different columns and
different data.
SELECT first_name FROM student_details;
NOTE: The commands are not case sensitive. The above SELECT
statement can also be written as "select first_name from
students_details;"
You can also retrieve data from more than one column. For
example, to select first name and last name of all the students.
SELECT first_name, last_name FROM
student_details;
You can also use clauses like WHERE, GROUP BY, HAVING, ORDER BY
with SELECT statement. We will discuss these commands in coming chapters.
NOTE: In a SQL SELECT statement only SELECT and FROM statements
are mandatory. Other clauses like WHERE, ORDER BY, GROUP BY, HAVING are
optional.
